code: def test_save_load_rgba(tmpdir):
      fname = tmpdir.join("mahotas_test.png")
      img = np.arange(256).reshape((8, 8, 4)).astype(np.uint8)
      freeimage.imsave(fname, img)
      img_ = freeimage.imread(fname)
      assert img.shape == img_.shape
      assert np.all(img == img_)
  
file_path: mahotas/mahotas/tests/test_freeimage.py
imports: import numpy
  from os import path
label_desc: Use image node_id 4 for calling a global function with example usage: test_save_load_rgba(tmpdir) without return types